A printhead die in an inkjet pen or print bar includes a plurality of fluid ejection elements on a surface of a silicon substrate. Fluid flows to the ejection elements through a fluid delivery slot formed in the substrate between opposing substrate surfaces. While fluid delivery slots adequately deliver fluid to fluid ejection elements, there are some disadvantages with such slots. From a cost perspective, for example, ink delivery slots occupy valuable silicon real estate and add significant slot processing cost. In addition, lower printhead die cost is achieved in part through die shrink, which is associated with tighter slot pitch and/or slot width in the silicon substrate. However, shrinking the slot pitch adds excessive assembly costs associated with integrating a small die into the inkjet pen. Structurally, removing material from the substrate to form an ink delivery slot weakens the printhead die. Thus, when a single printhead die has multiple slots (e.g., to improve print quality and speed in a single color printhead die, or to provide different colors in a multicolor printhead die), the printhead die becomes increasingly fragile with the addition of each slot.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.